The present invention relates generally to circuitry and methods for powering a light source such as an LED load. More particularly, the present invention relates to methods for dynamic adjustment of power parameters for LED drivers.
Light emitting diode (“LED”) lighting is growing in popularity due to decreasing costs and long life compared to incandescent lighting and fluorescent lighting. LED lighting can also be dimmed without impairing the useful life of the LED light source.
LED loads are DC current driven, so a DC-DC or AC-DC converter is needed to regulate the current going through the LED to control the output power and luminance. An exemplary dimmable LED driver 100 is represented in FIG. 1. As shown, a typical four-wire output 0-10v controllable AC-DC converter 114 is coupled between the AC mains input 112 and the LED load 116. This AC-DC converter regulates the DC current going through the LED lighting module 116 and also receives control signals from a dimming control block 118 to set the output current dynamically. Typically, a DC voltage 120 is provided, for example, from a remote dimming control source as the input of the dimming control block 118. The dimming control block will sense the voltage level 120 and set a control signal 122 for the reference of LED output current according to a preset relationship between the two values 120, 122.
To those in the field of LED fixture design and manufacturing, it would be very desirable to provide the same LED drivers for installation across a wide range of light fixtures, and then be able to adjust output current to the rated current of respective LED loads for each specific fixture without powering the whole system up.